"Experience is what you get when you don't get what you want."
And its corollary:
"Most of what we want we don't need--most of what we need we don't want."
I have come to the conclusion that very little of what I buy second hand for ham gear will be 'as advertised' or functional when I get it home. It does not seem to matter whether I use FleaBay, the fora with classifieds, or find a treasure at a hamfester. Its appearance is not an indicator of its functionality either--as I opt for the better looking junk.
HOWEVER--each and every piece ends up being a wonderful bench experience in repair, rehab, and reuse. I have come to the conclusion that if something is perfect coming in the door there is little fun to be had.
The newest case in point is my 'new' Shure 55SW dynamic mic garnered from FleaBay. The world has gone completely nuts. Anything over 20 years old is now called "vintage", and is a 'rare' 'classic'. This is of course populist marketing to drive the price of some old and common piece of shit up through the roof... The trouble with any of the 55x series of mics is that they have been inexorably linked with Elvis Presley. All flavors--from the 1939 'Fatboy' all the way to the current 55SH II are called the "Elvis Mike." Somehow this commands unreasonable prices for a very common PA and BCB service microphone.
So I scored my latest treasure at $115 shipped. I knew that the foam was disintegrated rubbish--obvious from the pics. What the seller failed to disclose was that the cartridge rattled around inside the housing like a liberal's brain at a budget meeting.
But wait! Why do I think I need the damned thing in the first place? It all has to do with this aye-yem ballbuster station that is being put together with the Valiant. 55SW into a Samson C-Valve pre, fed to a 2 channel Macintosh (vintage & classic) EQ mixer, and finally at line into a RS MPA-80 80 watt amp. Then through a bit of iron (220V to 12V filament transformer) direct to the modulator plates! Can you hear me now? :cool2:
Disassembly revealed the ugly truth. The rubber shock mounts had DISSOLVED into nothingness--except for trails of black hardened gunk. Chemical outgassing corroded solder points--along with several screws that twisted off on removal. And BS rubbish everywhere from the foam pop screen. Time to clean and test.
The cartridge was hooked to the scope (along with the spectrum analyzer). Fired up the HP 202C into a Kenwood home theater speaker. Started tracking points along the factory spec curve. Yowza! Cart was good, and within specs. The cleanup began.
Next was the reconstruction of the rubber mounts. A 2" neoprene fender washer provided the goods necessary. Sections were cut to fit the mounting recesses, and glued with black silicone. While that is drying, a full cleanup of the housing and other components was done. This is where it gets interesting and expensive. New foam pop and stand mounting hardware was gotten from Full Compass. A sheet of stainless steel screen from NAPA. MC2M (Amphenol) connectors now made by Cooper from Allied Electronics. Beer by Southern Tier Brewing Company (IPA).
Whatta mess, and what fun! I still need to bore out the screws that wrung out. Somehow the project bought a new set of Channel Lock 440 & 420 pliers (don't ask...).
Photos to follow later...